Old wallet.dat from 2014 - how can I open/use it on new Mac?

[larrysing]

Total Newbie here. I mined some Bitcoin using Bfgminer back in 2014, and I just found the old external drive with the info on it. If I remember correctly, I think it was about .4 Bitcoin that got mined.

I have an old wallet.dat file and my 12-word passphrase for opening it, but really nothing else.

No bitcoin app on my Mac.

What can I do to get that thing opened to see how much bitcoin is there?  Is that all I need?  Or am I grossly misinformed as to how this all works?

Thanks much.

[ibminer]

Do not share your phrase or .dat with anyone. I'd assume this is a 12 word seed you have (BIP39)... the easiest way to access it is probably using Electrum:


guide: https://bitcoinelectrum.com/restoring-your-standard-wallet-from-seed/
electrum: https://electrum.org/#download

edit: I would also make backup copies of the .dat before doing anything with it.

[hugeblack]

You need to prepare several copies of the wallet.dat file, keep them in a safe place.
Do not send this file to anyone or tell anyone about the 12-word passphrase.

What wallet did you use, was it blockchain.info/bitcoinCore/electurm?

Open one of the copies, if you find incomprehensible texts, this means that the file is encrypted and you need the password.

What do you mean by 12-word passphrase, if it is not the password to decrypt wallet.dat, compare those words with the words in this list https://github.com/bitcoin/bips/blob/master/bip-0039/english.txt.

[larrysing]

I understand about the backup and the sharing, thanks.

I'm assuming the 12-words are the words to decrypt the wallet file, right?  I have one other long password in my saved information.

But - two of my words are NOT in that list you referred me to. Is it possible the list has changed since 2014?

I have no memory of what wallet I used. I may not have ever created a wallet, just mined the Bitcoin. It that possible?
If I created a wallet, it was with whatever Bfgminer used. I looked on that Mac and there was no Bitcoin software installed - I just used the webpage to mine the Bitcoin with Bfgminer.

So, I need more guidance, please, thanks folks!

I think the rules here are that you can't offer payment for assist services, so...

[ibminer]

I understand about the backup and the sharing, thanks.

I'm assuming the 12-words are the words to decrypt the wallet file, right?  I have one other long password in my saved information.

If you were using Bitcoin Core, which sounds more likely now since 2 of your words are not in the list, it could be just a 12 word password for encrypting, since core never used a seed phrase to my knowledge.

Is it possible the list has changed since 2014?

While it is possible BIP39's word list could change in theory, to my knowledge it never has and probably never will.

I have no memory of what wallet I used. I may not have ever created a wallet, just mined the Bitcoin. It that possible?

There were various ways to mine back then but most were using pools, and most pools had a website, or some way, to provide a payout address to those mining for the pool. Any earned coins would have went to whatever address you specified, which I am assuming is part of the wallet you found, but maybe not. A wallet is ultimately needed for an address to be created for the payout. I recall pools sometimes holding the coins on their site (in their own wallet), and sometimes there would be a threshold for releasing a payout, but either way it should have went back to a wallet and address you controlled one way or the other.

If you didn't create the wallet with Core or something else local on the machine, maybe a brainwallet?  Or maybe some sort of custodial/web wallet that was out there at the time? (which would not have been the best option)

If I created a wallet, it was with whatever Bfgminer used. I looked on that Mac and there was no Bitcoin software installed - I just used the webpage to mine the Bitcoin with Bfgminer.

I don't recall using Bfgminer myself, but it would have just mined, probably for a pool... it is not wallet software.

I think the rules here are that you can't offer payment for assist services, so...

Not sure I've heard that one before, unofficial forum rules are here.

IMO, the main thing you don't want to do is give the wallet and/or info. over to someone offering some service to help you, since it can be an easy way to lose whatever is on the wallet, if there is anything on it. IMO, you really want to try and do this yourself. It may be worth installing Bitcoin Core and seeing if it will open a copy of the wallet file you have.

The technical support board may also be a better place to ask this question, or move the thread there for more help.

[Porfirii]

This can sound a little stupid, but: are you sure that the 12 words aren't the seed (it was mentioned before that not with core, but still...).

If that was the case, you wouldn't even need your wallet.dat.

Have you tried just importing them into Electrum, and perhaps voilà?

[hugeblack]

I understand about the backup and the sharing, thanks.

I'm assuming the 12-words are the words to decrypt the wallet file, right?  I have one other long password in my saved information.

But - two of my words are NOT in that list you referred me to. Is it possible the list has changed since 2014?

Since it's not a BIP wallet seed, it's probably https://login.blockchain.com/beta/legacy-pages/forgot-password.html or https://en.bitcoin.it/wiki/Brainwallet .
Your chances of recovering your coins seem better via wallet.dat, so download pywallet from Github using ---> https://github.com/jackjack-jj/pywallet and then use this code

Code:

python pywallet.py --dumpwallet --wallet=WALLETFILE

It will work if you remember your password.

This thread^[1] has a better explanation and you can create a topic in technical section if any problem occurs.

[1] https://bitcointalk.org/index.php?topic=5449521.msg62119385#msg62119385